Extraction of tobacco with fluorochlorohydrocarbons



Patented Jan. 7, 1941 EXTRACTION F TOBACCO WITH FLUORO- CHLOROHYDROCARBONS William w. Rhodes, Philadelphia, Pa, assignor. by mesne assignments, to Kinetic Chemicals, Inc., a corporation of Delaware No Drawing. Application February 14, 1938, Serial No. 190,495

4 Claims. (Cl. 131-443) This invention relates to the treatment of The fluoro-chloro-methanes of the above list tobacco, more particularly it relates to the imrepresent the preferred compounds and of these provement of tobacco by solvent extraction of I prefer the monofluorochloromethanes. undesirable components. The selective action of these compounds as to This invention has for an object the improvetarry matter is illustrated by the following table: 5 ment of tobacco by extraction of undesirable lmpurities. A further object is the extraction of P fi P9 c at undesirable constituents from tobacco without a i? nic otin Ratio of impairing the desirable properties of the same. Compound 'if gf removed, it; A still further object is to reduce the fire and A a B co 6 10 health hazards encountered in the solvent extraction of tobacco. Other objects will appear 4 9 0 3 16 hereinafter. 2'. 9 0: 1 29 The aboveand other objects are accomplished CH0] F by the following invention which comprises Mam ]ifiiiriIIIIIIIIIIIIIIIII 016 115 1.4 treating tobacco with a solvent which has a preferential action upon the tarry constituents. The extraction can be performed on dry or More particularly these objects are accomplished moist tobacco, it can be performed p P extracting tobacco in the form of leaves bacco which has been treated with other agents. In any Qther Physical state in which it m i t The extraction can furthermore be performed at 20 such as aftFr grinding other Processmg 71th difierent stages of the preparation of the tobacco an aliphatic fiuorochlorohydrocarbon solvent. for use. The followin example illustrates the The fiuumcmorohydmcarbc'ns used are extraction of tobacco which has been pretreated ably those which have relatively low boiling with ammonia;

points, for example, below 100 C.

The invention will be further understood but Example III is not intended to be limited by thfi following one hundred pounds of uncured leaf tobacco x mp was moistened with dilute ammonia solution Example I (about 0.5% ammonia) and extracted in this One hundred pounds f l f t b w condition with 200# of CClzFz. This treatment tracted in a large vessel at a temperature of 20 o e about 30 of the tarry matter and Over. C. with monofluorotrichloromethane. The s01- 55% 0f the mcotlne Originally in the tobaccovent was found to contain a high amount of The Separation of e o e t from e 6 tarry matter and a relatively small amount of trfwted material may be accompl y Simple nicotine. The resulting tobacco after complete dlstillation- The residual v n ay e removal of the solvent was good in appearance moved m the 00118-000 y passing Other and had xcellent, smuking properties inert gases over the treated tobacco or by a sim- Emmpze H ple warming of the treated mass to volatilize the solvent.

one hundred Pmmds of shredded tobacco was The quantity of solvent which will be used de- 40 countercurrently extracted at a temperature of pends largely upon the results desired If a 20 C. m0n0fl110r0d10h10r0methane under maxjIn-um removal of tar is desired be Pressure- The Savant was found upon Subse' preferable to use a larger quantity of solvent or quent treatment to wntain a large amount of to treat the same in a countercurrent system.

tarry matter and minor amounts of nicotine The results reported in the above table were ob- The tobacco was of good flavor Odo! and tained with a solvent tobacco ratio of 10 to l Peamnce and had smolfing characteristicsbut this ratio is merely illustrative of the process Other fluorochloro-aliphatic hydrocarbons can and t a limitation.

be substituted for the Specific ones described in The temperature to be used may Vary over a the preceding examples with equally good wide range and depends upon not only the solsults- Among the useful compoundsare vent chosen but the pressure employed. Thus CHClFz CzHClF C2H3C1Fz the extraction may be carried out between -40 CzHzClzFz, CzHClaFz CzHaClzF' and +100 Cpand preferably between -10 and cmzclr'a CzClaF'a CHzClF +50 C. The particular temperature chosen de- CzHClzFa pends upon the particular solvent used and the which the extraction is carried out will depend entirely on the solvent and temperature at which the extraction is performed. As a general rule the pressure should at least be sumcient to keep the solvent in the liquid state. For example, it CFzClz is used as the solvent at a temperature of 309 C., the pressure will be about 98 pounds per square inch gauge, while it C2F4Cl2 is used at this temperature the pressure necessary will be only about 22 pounds per square inch gauge.

This invention presents the advantage that fire and health hazards which are encountered by the use of lower alkyl chlorides are eliminated. A further advantage resides in the fact that the solvent may be quickly removed from the tobacco at low temperatures. thus obviating the higher temperatures necessarywith other solvents. Since overheating or tobacco is very deleterious, this'advantage is of considerable importance. A still further advantage is the preferential solvent action exhibited by these solvents on theundesirable tarry matter found in tobacco. Other advantages reside in the combination of non-inflammability, low boiling point, non-toxicity, non-corroslveness to equipment, and good solvent action on tars..

As many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that we do not limit ourselves to the specific embodiments thereof except as defined by the appended claims. f

I claim:

1. The process which consists of subjecting tobacco to a liquid phase extraction with a lowboiling halogenated solvent taken from the class consisting of the normally gaseous fluorochloromethanes.

2. The process which consists of subjecting tobacco to a liquid phase extraction with dichlorodlfluoromethane.

3. The process which consists of subjecting tobacco to a liquid phase extraction with dichloromonofluoromethane.

4. The process which consists of subjecting tobacco to a liquid phase extraction with trichloromonofluoromethane. I

WILLIAM W. RHODES. 

